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A263310
Numbers n such that p=6*n+1, q=6*p+1 and r=6*q+1 are primes.
1
10, 25, 55, 61, 101, 125, 156, 220, 221, 381, 391, 465, 475, 495, 576, 810, 891, 901, 975, 1060, 1145, 1396, 1430, 1630, 1650, 1726, 1795, 1811, 1881, 1885, 1915, 2196, 2265, 2335, 2391, 2405, 2456, 2536, 2575, 2636, 2651, 2820, 2911, 2915, 2951, 2965, 3051, 3211, 3245, 3335
OFFSET
1,1
COMMENTS
Subsequence of A263309 (and as such also of A024899).
MAPLE
isA263310 := proc(n)
return isprime(6*n+1) and isprime(36*n+7) and isprime(216*n+43) ;
end proc:
for n from 1 to 3000 do
if isA263310(n) then
printf("%d, ", n);
end if;
end do: # R. J. Mathar, Oct 17 2015
MATHEMATICA
Select[Range[10000], PrimeQ[p=6*#+1]&& PrimeQ[q=6*p+1]&& PrimeQ[r=6*q+1]&]
PROG
(PARI) for(n=1, 1e4, if(isprime(p=6*n+1)&&isprime(q=6*p+1)&&isprime(6*q+1), print1(n", "))) \\ Altug Alkan, Oct 17 2015
CROSSREFS
Sequence in context: A022670 A072277 A283243 * A063424 A137930 A251310
KEYWORD
nonn
AUTHOR
Zak Seidov, Oct 13 2015
STATUS
approved